Anchor dragging alarm control based on anchor inclination

ABSTRACT

An inclination-sensitive switch is operatively secured to a part of an anchor. The switch is open when the part is oriented such that the anchor grabs the bottom. When the orientation of the anchor part exceeds the horizontal by a predetermined value, corresponding to that orientation when the anchor is freed from the bottom, that switch is closed to actuate an alarm.

United States Patent Inventor Leonard Schneider Beaver Brook Road, Lyme,Conn.

Appl, No. 808,487

Filed Mar. 19, 1969 Patented May 18, 1971 ANCHOR DRAGGING ALARM CONTROLBASED ON ANCHOR INCLINATION 9 Claims, 4 Drawing Figs.

US. Cl 340/29, 200/61.44, 1 14/206 Int. Cl G08g 3/00 Field of Search340/29 (D);

[56] References Cited UNITED STATES PATENTS 2,369,054 2/ 1945 Kehrer340/29 2,507,986 5/1950 Liss ZOO/61.44

Primary Examiner-Kathleen H. Claffy Assistant Examiner-Jan S. BlackAtt0rneyJames and Franklin E ABSTRACT: An inclination-sensitive switchis operatively secured to a part of an anchor. The switch is open whenthe part is oriented such that the anchor grabs the bottom. When theorientation of the anchor part exceeds the horizontal by a predeterminedvalue, corresponding to that orientation when the anchor is freed fromthe bottom, that switch is closed to actuate an alarm.

' ANCHOR m me ALARM CONTROL BASED ON ANCHORIYNCLINA'YIION ment with thebottom.

When a boat is stopped and itis desired that it'remain in one place, ananchor is dropped. The anchor flukes engage or dig into the bottom tosecure .the boat in position for as long a period as it desired. Highwinds, turbulent seas or shifts in tide or .current often causethe-anchorto become freed from the bottom and to drag therealong. Whenthis occurs, the boat is no longer secured in position and drifts,creating a potentially dangerous, and often an emergency, situation forthe crew.

it is readily apparent that if the anchor is so released andis dragging,the crew ofthe boat must be quickly alerted. This is especially-trueduring the night hours when the crew may be sleeping. 1 The problem ofanchor dragging is somewhat complicated 'by the fact that theboat mayswing around the anchor if the wind or .tide changes but the anchor maystill dig into the bottom and hold the boat in-position. It may well bedesirable that an alarm be given when such a shift in tide or windoccurs, so that the crew can be alerted to check the situation ifappropriate, but-an alarm given upon this occurrence should be readilydistinguishable from the alarm indicating actual anchor dragging. Ashift .in tide is expected and may not create a dangeroussituation, 'butany anchor dragging is aserious problem which must be brought positivelyto the attention of thecrew. v

ln arare numberof cases, the anchor may be dug into the bottom where thebottom has an excessively steep downward declivity. Thiscreates atenuous and insecure retention of the anchor in the bottom which greatlyincreases the possibility of the anchor dragging when compared to thesituation in which the anchor engagement with the bottom 'is' made at amore level location. Thus an alarm indicating the engagement of theanchor with an excessively sloping part of the bottom is also useful toinfonn the crew that it is anchoring in a potentially dangerouslocation.

It is a further object of the present invention to provide ananchor-dragging alarm for use on boats which provides a warning ofanchor dragging in a manner which can be distinguished from the mereshifting of the position of the anchor on the bottom.

It is another object of the present invention to provide ananchor-dragging alarm which provides an indication when the anchor isdug into the bottom at an angle exceeding a predetermined safe value forsecure anchor retention.

It is also an object of the present invention to provide a lightweight,economical, and reliable anchor alarm system which can be readilyincorporated onto the anchor conventionally provided in boats. 1

To these ends, the present invention provides an anchordragging alarmsystem inwhich an inclination-sensitive switch is operatively secured toa part of an anchor in a manner such that when that part departs from ahorizontal. orientation by a predetermined extent, the extent is closedand is effective-to actuate an alarm located'on the vessel. Theactuation of the alarm provides an indication to the boats crew thatthis condition has occurred. For many anchors, when their flukesdisengage from the bottom their shank is vertical or nearly so, whilewhen their flukes dig into the bottom their shank is horizontal ornearly so. For such anchors the inclination-sensitive switch may bemounted on or operatively connected to that shank.

Various alarm system have been proposedin the past to indicate thereleasing of the anchor from the bottom and the ensuing drift of thevessel after it has been so released. A great majority of these systemsrequire the use of a secondary or auxiliary anchor. The auxiliary anchoris operatively associated with various types of relatively complexmechanisms.

I The alarm when actuated provides an indication of vessel driftrelative to the bottom by sensing the movement of the boat with respectto the auxiliary anchor. The disadvantages associated with these knownsystems are apparent. First, is the requirement of a secondary anchorwhich must be separately carried on the boat and separately droppedalong with the main anch'or. Second, additional relatively bulky andcomplex .equipment is required to sense the relative movement of theboat with respect to the secondary anchor and to produce the warningindication of such drift. Third, the known drift alarm systems requirethat the boat drift for an appreciable distance before the alarm isgiven. lt is conceivable that this required drift may itself beimpermissible for the safety of the boat and itscrew.- p 1 For owners ofsmall pleasure craft space for the auxiliary equipment required by theknown alarm systems is not usually readily available. The cost of anyadditional equipment is a major factor, as is the ease and reliabilityof operation of that equipment. As a result, the known alarm systemshave met with only a reluctant and limited acceptance by pleasure craftowners.

It is the prime object of the present invention to provide an anchordrift alarm system for a vessel having an anchor which i liable inoperation.

The anchor shank may also be at an inclined position relative tothehorizontal, thereby to cause the switch to close, when the anchor is duginto a part of the bottom having a downward declivity greaterthanapredetermined safe value for secure anchorretention. in either event,the warning will be given to the-crew that an unsafe .condition existsand that corrective measures should be quickly initiated.

member is freely movable within that chamber, sothat when i the anchorpart to which the housing is secured is moved to its predeterminedangular position for switch closing, that'conducting part moves intoengagement with the switch contacts to close the switch and actuate thealarm.

- 1 While the anchor-dragging alarm system of the present invention ishighly useful for practically all types of anchors con ventionally usedon small boats, it is particularly useful in anchors of the Danforthtype in which the flukes are pivotal with respect to the shank. When theflukes are dug into the bottom, the shank normally lies substantiallyhorizontally along the bottom, being held in that position by the weightof u the chain interposed between the free end of the shank and theanchor line. When the flukes are pulled from the bottom, that is, whenthe anchor is starting to drag, the shank will, move from its horizontalposition and will assume a substantially vertical position which, asindicated above, closes the switch and actuates the alarm on the boat.

To the accomplishment of the above, and to such otherobjects as mayhereinafter appear, the present invention relates to a control for ananchor-dragging alarm system'as'defined in the appended claims and asdescribed in this specification, taken together with theaccompanying-drawings, in which:

FIG. 1 is a side elevation of a boat anchored in a body of water andillustrating the anchor-dragging alarm system of the present invention;

FlG.'2 is a side elevation of an anchor of the Danforth type with whichthe alarm system of this invention is incorporated;

FIG. 3 is a cross-sectional view, on an enlarged scale, taken designated14 secured to the boat by means of a line 16. As

ehown best in FIG. 2, anchor 14 is herein shown as being of theDanforth-type which comprises a pair of flukes l8 and-a shank pivotallymounted on a stock 22. However, it willbe understood that the alarmsystem of the present invention may be used to equal advantage with any,type of conventional chor, and is'in no way limited for use solely on aDanforthtype anchor.

v i As shown in H6. 3-, switch 22 comprises a rectangular housing 24madeof a lightweight, noncorrosive, and nonconducting materiaL'suchas'lucite plastic, which is mounted on an interrnediate portionof shank20 as by a bracket 26 the ends of which are secured together by means ofa fastening element, 1

such as a rivet 28 (FIG. 4). An interior chamber 30 having'asubstantially diamond-shaped cross sectionis formed within housing 24.Apair of normally unconnected contacts 32 and 34 are secured to the wallof chamber 30 at a location near the outboard or right-hand end of thechamber by anysuitable rheans, or they may as, shown in Fl'G. 3, bepartially embedded in the plastic material of housing 24 so that theirouter sur faces are in com'municationwith chamber-30. Apair ofconductors 36 and 38 are respectively connected to the contacts 32 and34 and extend through passages formed within the interior of housing 24to the'inboard or"left.-hand end of the housing, andvpass out of thehousing through an opening 40 into the interior of a flexible,lightweight,- tubing42 made of "a substance such as neoprene which doesnot corrode in a salt of housing 24 along the length of line,l6 to theboat; Conduc tors 36 and 38 are received at the boat and areconnected tothe circuit of-an alarm system 44 located at any convenient location onboat 10'. That circuit comprises a suitable voltage source in operativecircuit connection with the conductors 3 6 38 and a device such as abuzzer, bell or the like.'When the ends of conductors 36 and 38,connected to contacts 32 and 34 respectively, are electrically connectedthe alarm circuit'is closed and'the alarm is actuated.

, water environment. Tubing 42 extends from the inboard end pivot aroundthe stock 22 and dig into the bottom at the opposite side of'the stock.Accordingly, for-a short duration of time, shank 20 will pivotalong withflukes l8 around stock 22 until shank 20 reassumes its horizontalposition. However,

during the interval in which shank 20 is moving in thismanner,

' it temporarily assumes a position away from the horizontal to causeball 46 to roll into electrical connection with contacts 32 and 34,thereby causing a temporary actuationof the alarm dug into the bottom,and there is no need for them to take corrective' measures. However, ifthe alarm continues to sound for alonger period of time, the crew isthen made aware that the anchor itself is dragging-along the bottom andthat the boat is either drifting or will soon begin to'drift into deeperand more dangerous waters. I i

In some instances itmay be desired that the same alarm, a continuousone, be given when the anchor shifts as when it actually drags. This canreadily be accomplished by providing a latching relay in the alarmsystem, therelay being actuated to latching position whenever thecircuit is closed between contacts 32 and-34 and the relay beingeffective when latched'to sound the alarm.

Sometimes the initial dropping of the anchor causes the flukes to engagethe bottom at alocation at which the bottom is sloping either downwardlyor upwardly at an angle exceeding a safe declivity for secure-anchorretention. When this occurs shank 20, weighed down by chain 48 and itsown weight, will rest on-"the bottom at an angle corresponding to thedeclivity of the bottom. I

To provide. an indication of this potentially dangerous situation asecond pair of contacts 32a and 3411' are provided at the left end ofchamber 30. Thesec'ontacts are respectively'electrically connected 'toEonductors 36 and 38'and are in effective parallel circuit relationwithcontacts 32 and 34. When the angle of that -declivity.-of the shank20 exceeds the predetermined value in either direction (i.e. upwards ordownwards),

To this end a conducting member In the form of a metallic ball 46 isarranged for free, rolling movement within "the chamber 30. When housing24 is in a substantially horizontal position, ball 46 rests in the lowerapex of the diamond of chamber 30 as shown in the solid-line position ofball 46 in FlG. 3. Returning toFlG. 1, his seen'tha't when flukes l8 ofanchor 14 are dug into the bottom, shank 20- lies in a substantiallyhorizontal position as a result of its own' weight as well as theweight of a chain '48 which may be interposed-between the free end ofshank 20 and line 16. At this horizontal position of shank 20, housing24 is in a correspondinglyhorizontal position and the conducting ball 46remains atits lowermost position within chamber 30, shown in FIG. '3. Asa result, contacts 32 and 34 remain unconnected to one another. Ifthe'boat shifts positionsufficiently to lift the shank 20 to its morenearly vertical broken line position in FIG. 1, the flukes l8will bepulled from the sea bottom and the anchor will no longer 20, also movesaway from the horizontal towardsa nearly vertiball 46 is caused to rollinto'the space either between contacts 32 and 34, or contactsI32a and34a depending on which end of the shank (i.e. the fluke-connected or thechain-connected) is above the other end. when this occurs, the contactsso engaged by ball 46 are electrically connected and the alann circuitis closed as described above, to actuate alarm system 44. The criticalangle of declivity of the'bottom which will cause ball 46 toroll intocontact with one of the contact pairs is indicate'd as angle a in FlG.3, which is approximately one-half the-apex angle along the major orhorizontal axis of chamber 30. 1

For these anchoring conditions at which anchor retention is at bestuncertain and unreliable the sounding of the alarm indicates apotentially dangerous anchoring situation even though the flukes .18.may still be dug into the bottom to anchor the boat in position. Thecrew is thus alerted that the anchor must be released and the boat movedto a new position where anchoring can be effected at a-more levelportion of the bottom which will ensure a. more secure retention of theanchor. t

' The specific inclination-sensitive switch here illustrated is I butone of many different types which could be used. Penducal position. Thisraises the inboard end of housing 24 above its outboard end. When thedeviation of shank 20 andhousing 24 from a horizontal position exceeds apredetermined value (c.g. 20) the ball 46 will roll along'the inner wallof chamber 30 until it 'seats between contacts 32 and34, thereby toelectrically connect these contacts. As described above, this causes theactuation of the alarm system 44, which in turn provides thedesiredindication of anchor release and dragging.

' For a Danforth'type of anchor, as shown in FIGS. 1 and '2, it

may occur that a shift in the tide may cause the flukes [8 tolur'n-actuated and mercury-actuated switches are typical of the knownavailable switch types. Y

' The anchor-dragging alarm system control of the present invention thusprovides a reliable and substantially instantaneous indication of theorientation of the anchor in a positionsuch that its flukes are notdigging into the bottom. The anchor alarm system of this invention isreadily incorporated with a conventional anchor by means ofalightweight'and economical switch-housing readily mounted on a shank'ofthe anchor. The control can therefore be sold as an accessory to beattached to the anchor by'the' boat owner. Moreover, the

'5 alarm system is simple and requires little skill or experience to useto full advantage.

The alarm system of this invention is thus inexpensive to purchase andrelatively simple to install and-use, and provides a reliable andsubstantially instantaneous indication of anchor dragging. While only asingle embodiment of the present invention has been herein specificallydisclosed, it will be apparent-that many variations maybe made theretowithout departing from the spirit and scope of the invention.

lclaim:

l. A drift alarm control system for indicating drift in a water-goingvessel, said system comprising an anchor, a line adapted to lead fromthe vessel to said anchor, a housing, means effective to operativelysecure said housing to a part of said anchor, said part normally havinga given anchoring orientation relative to said sea bottom when saidanchor is operative, normally open first and second contact means insaid housing, connecting means operatively connected to said contactmeans and adapted to be operatively connected to an alarm located on thevessel, and means effective to sense the angular orientation of saidanchor part relative to a reference position corresponding to thatnormally assumed by said part when said anchor is operative on ahorizontal sea bottom and effective when said orientation varies fromsaid reference position by a predetermined value to operatively closesaid contact means, thereby to actuate the alarm..

2. The control system of claim 1, said housing having an inner chamberformed therein, said contact means being located at one one of saidchamber.

3. The control system of claim 1, inner chamber formed therein, saidcontact means being located at one end of said chamber, saidorientation-sensing means comprising conducting means articulatablydisposed in said housing having an said chamber and movable from a firstposition in which it does not engage said contact means, to a secondposition in which it is effective to engage and electrically connectsaid contact means when said housing orientation exceeds the horizontalby said predetermined value.

4. The control-system of claim 1, said anchor having a fluke adapted todig into the bottom, and a shank articulatably secured to said fluke,said shank defining said anchor part,

5. The control system of claim 4, said shank and said housing lying in asubstantially horizontal position with respect to the bottom when saidfluke is dug into the bottom, and at a position away from the horizontalby an amount exceeding said predetermined value when said fluke isreleased from the bottom.

6. The control system of claim 2, said anchor having a fluke adapted todig into the bottom, and a shank articulatably secured to said fluke,said shank defining said anchor pan.

7. The control system of claim 6, said shank and said housing lying in asubstantially horizontal position with respect to the bottom when saidfluke is dug into the bottom, and at a position away from the horizontalby an amount exceeding said predetermined value when said fluke isreleased from the bottom.

8. The control system of claim 3, said anchor having a fluke adapted todig into the bottom, and a shank articulatably secured to said fluke,said shank defining said anchor part.

9. The control system of claim 8, said shank and said housing lying in asubstantially horizontal position with respect to the bottom when. saidfluke is dug into the bottom, and at a position away from the horizontalby an amount exceeding said predetermined value when said fluke isreleased from the bottom.

1. A drift alarm control system for indicating drift in a watergoingvessel, said system comprising an anchor, a line adapted to lead fromthe vessel to said anchor, a housing, means effective to operativelysecure said housing to a part of said anchor, said part normally havinga given anchoring orientation relative to said sea bottom when saidanchor is operative, normally open first and second contact means insaid housing, connecting means operatively connected to said contactmeans and adapted to be operatively connected to an alarm located on thevessel, and means effective to sense the angular orientation of saidanchor part relative to a reference position corresponding to thatnormally assumed by said part when said anchor is operative on ahorizontal sea bottom and effective when said orientation varies fromsaid reference position by a predetermined value to operatively closesaid contact means, thereby to actuate the alarm.
 2. The control systemof claim 1, said housing having an inner chamber formed therein, saidcontact means being located at one one of said chamber.
 3. The controlsystem of claim 1, said housing having an inner chamber formed therein,said contact means being located at one end of said chamber, saidorientation-sensing means comprising conducting means articulatablydisposed in said chamber and movable from a first position in which itdoes not engage said contact means, to a second position in which it iseffective to engage and electrically connect said contact means whensaid housing orientation exceeds the horizontal by said predeterminedvalue.
 4. The control system of claim 1, said anchor having a flukeadapted to dig into the bottom, and a shank articulatably secured tosaid fluke, said shank defining said anchor part.
 5. The control systemof cLaim 4, said shank and said housing lying in a substantiallyhorizontal position with respect to the bottom when said fluke is duginto the bottom, and at a position away from the horizontal by an amountexceeding said predetermined value when said fluke is released from thebottom.
 6. The control system of claim 2, said anchor having a flukeadapted to dig into the bottom, and a shank articulatably secured tosaid fluke, said shank defining said anchor part.
 7. The control systemof claim 6, said shank and said housing lying in a substantiallyhorizontal position with respect to the bottom when said fluke is duginto the bottom, and at a position away from the horizontal by an amountexceeding said predetermined value when said fluke is released from thebottom.
 8. The control system of claim 3, said anchor having a flukeadapted to dig into the bottom, and a shank articulatably secured tosaid fluke, said shank defining said anchor part.
 9. The control systemof claim 8, said shank and said housing lying in a substantiallyhorizontal position with respect to the bottom when said fluke is duginto the bottom, and at a position away from the horizontal by an amountexceeding said predetermined value when said fluke is released from thebottom.